Heat oil in large skillet set over medium heat; cook chicken, curry paste, salt and pepper for 8 to 10 minutes or until chicken is browned.
Whisk together coconut milk and peanut butter; add to skillet along with frozen vegetables and diced tomatoes. Bring to boil; reduce to simmer and cook for 15 to 20 minutes or until chicken is cooked through and sauce has thickened. Serve over cooked rice and sprinkle with cilantro and peanuts.
Tip: Peanut butter can be replaced with soy nut butter for a nut-free alternative.